Beast and Man: The Roots of Human Nature (1979).
“Most of us always want to be different; better, prettier, richer, smarter, and so on. That's what makes us jealous of other people's advantages that we don't have. And that is also the reason why we are never satisfied and do not feel happiness.”
Related quotes
Commencement Address at Middlebury College May, 2001 http://web.archive.org/web/20030906163501/http://www.middlebury.edu/offices/pubaff/general_info/addresses/Fred_Rogers_2001.htm
Seminar at LeSEA Broadcasting Studios in South Bend, Indiana http://www.christianitytoday.com/music/interviews/2003/richmullins-hiatranscript1.html (February 1993)
Robert Fogel in: " Early Retirees Turn to Volunteer Work http://www.npr.org/templates/story/story.php?storyId=4970476," at npr.org. October 23, 2005.
Chap. 7 : Soften People’s Resistance by Confirming Their Self-opinion
The Laws of Human Nature (2018)